The primary focus of the current application is to develop a new device for PTX detection using computerized analysis of breath sounds. Pilot animal studies suggested that this approach may have high diagnostic power. The proposed human, animal, and mechanical experiments will utilize acoustic measurements and analyses that are designed to test feasibility, optimize the technique, and study audible-frequency acoustic wave behavior in the pulmonary system. Devices resulting from this technology are expected to be accurate, easy-to-use, radiation-free, inexpensive, rapid, portable, and safe. The long-term objective of this project is to develop techniques for the diagnosis of medical conditions using computer-assisted auscultation of body sounds. While the use of stethoscopes for medical diagnosis is common, this approach is skill dependent, can only provide qualitative information, and may suffer from inherent limitations of human ability to discern certain acoustic differences. The innovative nature of the proposed work is the implementation of simultaneous multi-sensor acquisition of body sounds combined with state of the art digital processing algorithms. The accumulated knowledge base and experience from the proposed work may be useful in developing a broad range of diagnostic technologies including cardiovascular, gastrointestinal, muscle, and joint applications. For example, earlier studies have suggested potential utility for diagnosis of such conditions as small bowel obstruction, pneumoperitoneum, vascular access compromise, coronary occlusions, and osteoporosis.